A Review on Minimum Quantity Lubrication for Machining of Difficult to Machine Materials

Abstract

There are lots of research happening in high speed machining especially for hard materials which find its applications in vast areas like aerospace, marine, automobiles etc. The main parameters which need to be taken care of while doing high speed machining are surface roughness and tool wear. To achieve high degree of surface finish and close tolerance in the work piece materials, care should be taken to select the right type of tool and lubrication. The conventional type flood lubrication system is found to be having more cost involved and also more time and work is involved in cleaning and disposal of used lubricants, which is also an ecological hazard. For high speed machining, reducing the temperature generated is the main concern by using suitable cooling system. In this regard Minimum Quantity Lubrication (MQL) has been found to be more effective compared to other lubrication systems. This paper presents a review of research work with regard to MQL and its systems with suitable additions for machining difficult to machine materials. An overview about different lubrication system types is presented, followed by some of the commonly used MQL systems. Further the different aspects related to use of MQL in different applications is presented, followed by the use of additives in MQL like use of nano particles is reviewed, to understand its effect on the performance of MQL. MQL with nano particles is more effective in reducing tool wear and surface roughness for all types of machining processes.